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3D additive-manufactured nanocomposite magnetic scaffolds: Effect of the application mode of a time-dependent magnetic field on hMSCs behavior

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Bioactive Materials 2017年第3期2卷 138-145页

作者： Ugo D'Amora Teresa Russo Antonio Gloria Virginia Rivieccio Vincenzo D'Anto Giacomo Negri Luigi Ambrosio roberto de santis Institute of Polymers Composites and BiomaterialsNational Research CouncilNaplesItaly Villa Betania Evangelical Hospital NaplesItaly department of Neuroscience Reproductive Sciences and Oral SciencesUniversity of Naples Federico IINaplesItaly Unit of dentistry Bambino GesùChildren's HospitalIRCCSRomeItaly

Over the past few years,the influence of static or dynamic magnetic fields on biological systems has become a topic of considerable *** has recently been implicated to play significant roles in the regulation of cell responses and,for this reason,it is revolutionizing many aspects of healthcare,also suggesting new opportunities in tissue *** aim of the present study was to analyze the effect of the application mode of a time-dependent magnetic field on the behavior of human mesenchymal stem cells(hMSCs)seeded on 3D additivemanufactured poly(3-caprolactone)/iron-doped hydroxyapatite(PCL/FeHA)nanocomposite scaffolds.

关键词： Additive manufacturing Scaffold Magnetic field Cell-material interaction

Application of ultrasonography-elastography score to suspect porto-sinusoidal vascular disease in patients with portal vein thrombosis

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 20-24页

作者： Stefania Gioia Adriano de santis Giulia d’Amati Silvia Nardelli Alessandra Spagnoli Arianna Di Rocco Lorenzo Ridola Oliviero Riggio department of Translational and Precision Medicine Sapienza University of RomeRomeItaly department of Radiological Oncologicaland Pathological SciencesSapienza University of RomeRomeItaly department of Public Health and Infectious Diseases Sapienza University of RomeRomeItaly

Background:Porto-sinusoidal vascular disease(PSVD)and portal vein thrombosis(PVT)are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal *** PVT may be a consequence of PSVD,in PVT patients at presentation,a pre-existing PSVD should be *** these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management,but it could be *** this setting ultrasonography may be valuable in differential *** aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and“pure”PVT and then to suspect PVT secondary to a pre-existing ***:Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse(ARFI).Results:ARFI was higher and superior mesenteric vein(SMV)diameter was wider in PSVD patients than in PVT ***,a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT(the area under the curve=0.780;95%confidence interval:0.690-0.869).Conclusions:A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.

关键词： Non-cirrhotic portal hypertension Porto-sinusoidal vascular disease Chronic portal vein thrombosis Liver stiffness Portal hypertension Acoustic radiation force impulse

Microbial Community with Potential for Metal Release Isolated from Palca Mine Tailings Pond in Peru

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Journal of Geoscience and Environment Protection 2024年第7期12卷 109-121页

作者： César Wilber Guzmán Moreno Bruno Karolski Solange Kazue Utimura roberto Castellanos Cabrera Jhon Albert Centeno Torres Daladier Miguel Castillo Cotrina Elisabete de santis Braga Dayana Sarai Gamonal Fermandez denise Crocce Romano Espinosa Joel Barbujiani Sigolo department of Sedimentary and Environmental Geology Institute of Geoscience USP So Paulo Brazil department of Chemical Engineering LAREX USP So Paulo Brazil CEPEMA Environment Training and Research Center USP So Paulo Brazil Facultad de Ciencias Universidad Nacional Jorge Basadre Grohmann UNJBG Tacna Per department of Physical Chemical and Geological Oceanography USP So Paulo Brazil Facultad de Ciencias Biolgicas Universidad Nacional Pedro Ruiz Gallo UNPRG Lambayeque Per

The improvement of microbial characterization has increased the comprehension of microbial population and their ability in the microbiological metal dissolution. Bioleaching processes have been expanded to use microorganisms for the recovery of metals from ores and wastes. This study introduces Palca mine tailings pond in Peru which turned into acid mine drainage (AMD). AMD is a source of microbial communities whose microorganisms may support the aqueous extractive metallurgy for metal recovery. Four samples of AMD were collected from different locations and the elemental characterization showed concentrations of metals, such as Cu, Zn, Al, Mn, and Fe. The pH of the samples showed variation between 1.9 - 6.8. Twenty-one microorganisms were isolated and selected according the cell morphology. 16s rRNA gene sequences identified five species of which three belong to the bacterial kingdom and two to the Fungi kingdom. Two of the bacterial species were ferrous ion oxidizing bacteria, identified as Acidithiobacillus ferriphilus and Acidithiobacillus ferridurans;and the other one a ferric ion reducing bacteria identified as Acidiphilium acidophilum. The fungi species identified were Rhodotorula sinensis and Exophiala xenobiotica, a filamentous fungus isolated for the first time from an AMD.

关键词： Acidophilic Microorganisms Acid Mine Drainage—AMD Bioleaching Process Metals Recovery Acidithiobacillus

Geophysical evidence of a large occurrence of mud volcanoes associated with gas plumbing system in the Ross Sea(Antarctica)

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Geoscience Frontiers 2024年第1期15卷 304-324页

作者： Martina Busetti Riccardo Geletti Dario Civile Chiara Sauli Giuseppe Brancatelli Edy Forlin Daniela Accettella Lorenza Barro Savonuzzi Laura de santis Aldo Vesnaver Andrea Cova National Institute of Oceanography and Applied Geophysics–OGS Borgo Grotta Gigante 42/c34010 SgonicoTriesteItaly

Seafloor and buried reliefs occur along continental margin of the Ross Sea(Antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome *** studies have proposed a volcanic or glacial origin for these formations,but these hypotheses do not account for all the available *** this study,we use morpho-bathymetric data,intermediate resolution multichannel seismic and high resolution chirp profiles,as well as magnetic lines to investigate these clusters of *** employing targeted processing techniques to enhance the geophysical characterization of the seafloor and buried reliefs,and to understand the underlying geological features,we propose that the reliefs are mud *** of these formations appear to be associated with a plumbing system,as indicated by acoustic anomalies linked to sediment containing *** formations are likely fed by clayey source rocks of Miocene ***,other reliefs might be the result of mud mobilisation caused by gravity instability and fluid overpressure.

关键词： Ross Sea Antarctica Mud volcanoes Gas plumbing system Gas hydrate Bottom Simulating Reflector

Diversity of beetle species and functional traits along gradients of deadwood suggests weak environmental filtering

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Forest Ecosystems 2023年第1期10卷 56-63页

作者： Marco Basile Francesco Parisi roberto Tognetti Saverio Francini Fabio Lombardi Marco Marchetti Davide Travaglini Elena de santis Gherardo Chirici Swiss Federal Research Institute WSL Zürcherstrasse 1118903BirmensdorfSwitzerland Swiss Ornithological Institute Seerose 16204SempachSwitzerland GeoLAB-Laboratory of Forest Geomatics Department of AgricultureFoodEnvironment and ForestryUniversita degli Studi di FirenzeFirenzeItaly Dipartimento Agricoltura Ambiente e AlimentiUniversita degli Studi del MoliseVia De Sanctis86100CampobassoItaly Fondazione per il Futuro delle Citta FirenzeItaly Dipartimento di Agraria Universita Mediterranea di Reggio CalabriaLocalita di Feo di VitoReggio Calabria89122Italy Dipartimento di Bioscienze e Territorio Universita degli Studi del MoliseContrada Fonte Lappone86090PescheItaly

Background: Gradients in local environmental characteristics may favour the abundance of species with particular traits, while other species decline, or favour species with different traits at the same time, without an increase in average species abundances. Therefore, we asked: do variations in species and traits differ along gradients of deadwood variables? Do species abundance and trait occurrence change with species richness within or between functional groups? Thus, we analysed the beetle assemblages of five forest sites located in Italy, along the Apennines ***: From 2012 to 2018 we sampled beetles and five deadwood types in 193 plots to characterise the deadwood gradient: standing dead trees, snags, dead downed trees, coarse woody debris, and stumps. We modelled beetle species relative abundances and trophic traits occurrences against the deadwood variables using joint species distribution ***: Out of 462 species, only 77 showed significant responses to at least one deadwood type, with a weak mean response across species. Trophic groups showed mostly negative responses to deadwood variables. Species abundance increased with species richness among sites only for phytophagous and saproxylophagous. Trait occurrence did not increase with species richness among sites, except for phytophagous and ***, trait occurrence changed significantly with species richness of several trophic groups within some *** found that increases in species richness do not result in decreases in species abundance of a given trophic group, but rather null or positive relationships were found suggesting low interspecific ***: Our findings suggest that in Mediterranean mountain forests there is still room for increasing the level of naturalness, at least for what concerns deadwood management. On one side, our findings suggest that competition for deadwood substrates is still low, on the other side they indicate that incre

关键词： Abundance Forest Italy Joint species distribution model Saproxylic Trophic group

The elegance of a macrophage

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Cellular & Molecular Immunology 2018年第3期15卷 196-198页

作者： Maria de santis Massimo Locati Carlo Selmi Rheumatology and Clinical Immunology Humanitas Research HospitalRozzanoItaly Laboratory of Leukocyte Biology Humanitas Research HospitalRozzanoItaly BIOMETRA department University of MilanMilanItaly

In the latest issue of Nature Immunology,Piccolo et al.1 elegantly explored the effect of coexisting interferon-γ(IFN-γ)and interleukin 4(IL-4)antagonistic signals on macrophage transcriptional and epigenetic profiles and,interestingly,identified a plastic cross-talk as opposed to mutually exclusive programs between M1 and M2 polarized *** results support the fascinating hypothesis that transcriptional and epigenetic reprogramming overcame genetics to drive the evolution of eukaryotic organisms.A rapid reshaping of chromatin acetylation redirected the expression of hundreds of genes under the control of a few transcription factors in response to two coexisting but opposing signals that indicated inflammation and its resolution simultaneously.

关键词： macrophage interferon inflammation

A WKNN-based approach for NB-IoT sensors localization

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Digital Communications and Networks 2023年第1期9卷 175-182页

作者： Ennio Gambi Linda Senigagliesi Andrea Barbaresi Matteo Mellini Adelmo de santis department of Information Engineering Universita Politecnica delle Marche60131AnconaItaly TIM S.p.A.-Business-Pre Sales Engineer 60100AnconaItaly

With the recent introduction of NarrowBand Internet of Things(NB-IoT)technology in the 4th and 5th generations of mobile radio networks,the mobile communications context opens up significantly to the world of *** means of NB-IoT,the mobile systems within 3GPP standardization introduce the peculiar functions of sensor networks,thus making it possible to satisfy very specific requirements with respect to those which characterize traditional mobile *** the functions of interest for sensor networks,the possibility of locating the positions of the sensors without an increase in costs and energy consumption of the sensor nodes is of utmost *** present work describes a procedure for locating the NB-IoT nodes based on the quality of radio signals received by the mobile terminals,which therefore does not require further hardware implementations on board the *** procedure,based on the RF fingerprinting technique and on machine learning processing,has been tested experimentally and has achieved interesting performances.

关键词： Narrowband Internet of Things(NB-IoT) Sensor localization Sensor networks RF fingerprint Positioning LTE

The Rise of Social Commerce and Collaborative Consumption: Value Creation in Consumer-to-consumer Share-based Marketplaces

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The Rise of Social Commerce and Collaborative Consumption: V...

作者： Gianluca de santis 复旦大学

学位级别：硕士

过去五年电子商务界经历了巨大变化,在此过程中消费者扮演的角色变得日益重要,显著带动了社会化电子商务的兴起,从而引发了协作消费这一社会经济现象的诞生。这篇论文旨在探索：在社会化电子商务和协作消费的双重推动下,客户对客户网络... 详细信息

过去五年电子商务界经历了巨大变化,在此过程中消费者扮演的角色变得日益重要,显著带动了社会化电子商务的兴起,从而引发了协作消费这一社会经济现象的诞生。这篇论文旨在探索：在社会化电子商务和协作消费的双重推动下,客户对客户网络市场的兴起这一现象,并深究这一市场领域的价值创造过程。尽管在学术和实际运用领域,众多研究、学术文章将目光集中在客户对客户网络市场,我通过研究发现现有的相关文献资料的侧重点取决于研究者个人兴趣、专业,因此大多集中在个别领域。这造成了现有文献既没有提供清晰明了的市场定义,又没有将社会化电子商务的多种不同形式予以呈现。我想这也许是因为社会化电子商务在今天科学技术创新日益加速的外界环境下,也在日新月异地进化革新着,而相关研究、文献无法跟上其革新的速度。基于以上几点,这篇论文在现有文献的基础上,将作出以下两点贡献：首先,在各种社会化电子商务之间架起桥梁,将C2C市场定位于社会化电子商务和协作消费这两个框架其中,同时明确地界定这两种现象,提出对社会化电子商务的分类。论文的第二部分则将全部目光转向价值创造模型的建立上。这一部分基于对现有相关文献的深度解读和对七个案例研究的深度分析。现有相关文献包括：交易成本经济学（Williamson,1979,1983）,创造性破坏理论（Schumpeter,1942）,资源观点论（Barney,1991）,以及蓝海战略（Kim和Mauborgne,2005）。七个实际案例包括：Airbnb Inc., RelayRides Inc., Zopa Ltd., thredUP Inc., Zilok SAS, TaskRabbit Inc.以及Landshare. 由于C2C共享机制网络平台仍然是一个相对新鲜的现象,定性和归纳的案例研究应该是初期理论建立阶段比较合适的方法（Eisenhardt,1989）. 对这些C2C共享机制市场领域公司的分析显示：无论这些公司属于何种行业、提供何种产品和服务,它们都有相似的价值曲线。这些价值曲线源于相似的战略性创新,并且更重要的是,它们拥有类似的价值驱动。在此发现基础上,我得出了八种价值创造来源,并将它们组织归纳进了我提出的C2C共享机制市场领域价值创造的模型里。这些价值创造来源分别是：效率、互补性、创新度、锁定、信任度、社区效应、数据访问和非物质化。这一模型能对新兴行业创业人和传统公司经理提供有意义的启发：让他们对所在竞争市场的价值创造之动态结构和过程有深度认识,意识到所在市场的潜在机遇以及挑战。最后,结论部分对C2C共享机制市场的诞生对传统公司的影响进行探索研究,并目.提出一些竞争应对措施方面的建议,其中,部分建议基于对一些企业实际案例的分析。

关键词：社会化电子商务和协作消费值创造 Web 2.0的

Satellite Integration into 5G:deep Reinforcement Learning for Network Selection

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Machine Intelligence Research 2022年第2期19卷 127-137页

作者： Emanuele de santis Alessandro Giuseppi Antonio Pietrabissa Michael Capponi Francesco delli Priscoli department of Computer Control and Management Engineering“Antonio Ruberti”University of Rome La SapienzaRome 00185Italy

This paper proposes a deep-Q-network(DQN) controller for network selection and adaptive resource allocation in heterogeneous networks, developed on the ground of a Markov decision process(MDP) model of the problem. Network selection is an enabling technology for multi-connectivity, one of the core functionalities of 5G. For this reason, the present work considers a realistic network model that takes into account path-loss models and intra-RAT(radio access technology) interference. Numerical simulations validate the proposed approach and show the improvements achieved in terms of connection acceptance, resource allocation, and load *** particular, the DQN algorithm has been tested against classic reinforcement learning one and other baseline approaches.

关键词： Network selection HetNet deep reinforcement learning deep-Q-network(DQN) 5G communications